Today, Sunday 15 March, I've changed my mind. There's a crack in the plastic near the lens. Was it already there on Friday, I didn't see anything. As I mentioned below, the packaging was not sufficient. I'm obliged to keep the lens as I didn't notice it earlier. I can't prove whether the gap was already there, or whether it has widened. Fortunately this doesn't prevent me from taking photos, but I do mind having a lens that isn't quite as good as new.
On the other hand, the packaging in which I received it is a bit flimsy for a lens of this price.